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Author Mpakairi, K.S.; Muvengwi, J.
Title Night-time lights and their influence on summer night land surface temperature in two urban cities of Zimbabwe: A geospatial perspective Type Journal Article
Year 2019 Publication Urban Climate Abbreviated Journal Urban Climate
Volume 29 Issue Pages (down) 100468
Keywords Remote Sensing
Abstract Owing to the developments that exist in urban landscapes, urban areas experience climates that are different from their surroundings even when in the same climatic region. This is a prominent phenomenon in most urban areas and is commonly known as Surface Urban Heat Island (SUHI). An understanding of some of the drivers of SUHI is imperative for cities worldwide if they endeavor to suppress the socio-economic mishaps related to extremely high UHI. In this study, we sought to explain the drivers of SUHI in two developing cities in Zimbabwe using remote sensing data. We do this through the use of a classification and regression model. The model used climate, land descriptors and anthropogenic activity data as predictor variables against summer night land surface temperature. Using the coefficient of determination (R2) and the root mean square error (RMSE) for evaluation, modelled SUHI was strongly related to actual SUHI. We also found out that night-time lights, a proxy of anthropogenic activity, contributed more to summer night surface urban heat island as compared to other variables used in the study. This study adds more knowledge on the likely drivers of UHI for southern African cities. By identifying SUHI drivers in urban cities, it is plausible to formulate policies or initiatives that regulate extreme summer night SUHI.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2212-0955 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2497
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Author Ranzoni, J.; Giuliani, G.; Huber, L.; Ray, N.
Title Modelling the nocturnal ecological continuum of the State of Geneva, Switzerland, based on high-resolution nighttime imagery Type Journal Article
Year 2019 Publication Remote Sensing Applications: Society and Environment Abbreviated Journal Remote Sensing Applications: Society and Environment
Volume 16 Issue Pages (down) 100268
Keywords Remote Sensing; Ecology; Switzerland; Europe; orthophotography; viewshed analysis
Abstract The increase of artificial light in recent decades has led to a general awareness of the harmful consequences of light pollution on biodiversity. The artificial light is however rarely taken into account in the principles of developing ecological networks. There is currently no standardized method for integrating this darkness factor into ecological network modeling. We propose a methodology for the identification of the nocturnal continuum through an approach based on the automated extraction of light sources from nocturnal orthophotography and the modeling of their visibility within a territory. The model is applied to the transboundary region of the Geneva basin in Switzerland and allows for the integration of the darkness factor into the existing ecological networks. Although the analysis does not consider metric lighting data, a viewshed analysis allows for a first large-scale mapping of the nighttime continuum and highlights the areas benefiting from very low light pollution.
Address University of Applied Sciences and Arts, Route de Presinge 150, 1254, Jussy, Switzerland; jessica.ranzoni(at)hesge.ch
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2352-9385 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2687
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Author Fulbright, J.P.; Xiong, X.
Title Suomi-NPP VIIRS day/night band calibration with stars Type Journal Article
Year 2015 Publication Proc. SPIE 9607, Earth Observing Systems XX, 2015 Abbreviated Journal
Volume Issue Pages (down) 96071S
Keywords Remote Sensing; Suomi NPP; VIIRS DNB; calibration
Abstract Observations of stars can be used to calibrate the radiometric performance of the Day/Night Band (DNB) of the Suomi-NPP instrument VIIRS. Bright stars are normally visible in the Space View window. In this paper, we describe several potential applications of stellar observations with preliminary results for several. These applications include routine trending of the gain of the highand mid-gain stages of the DNB and trending the gain ratio between those stages. Many of the stars observed by the VIIRS DNB have absolute flux curves available, allowing for an absolute calibration. Additionally, stars are visible during scheduled lunar roll observations. The electronic sector rotations applied during the scheduled lunar observations greatly increases the sky area recorded for a brief period, increasing the observing opportunities. Additionally, the DNB recorded data during the spacecraft pitch maneuver. This means the deep sky was viewed through the full Earth View. In this situation, thousands of stars (and the planet Mars) are recorded over a very short time period and over all aggregation zones. A possible application would be to create a gain curve by comparing the instrument response to the known apparent stellar brightness for a large number of stars of similar spectral shape. Finally, the DNB is especially affected the mirror degradation afflicting VIIRS. The degradation has shifted peak of the relative spectral response (RSR) of the DNB the blue and the effective band pass has been slightly reduced. The change in response for hot stars (effective temperatures of over 30,000 K) due to this degradation will differ by about 10 percent from the response change of cool stars (below 3500 K).
Address Science Systems and Applications, Inc., USA
Corporate Author Thesis
Publisher SPIE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1260
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Author Cao, C.; Zong, Y.; Bai, Y.; Shao, X.
Title Preliminary study for improving the VIIRS DNB low light calibration accuracy with ground based active light source Type Journal Article
Year 2015 Publication Proc. SPIE 9607, Earth Observing Systems XX, 2015 Abbreviated Journal
Volume Issue Pages (down) 96070D
Keywords Remote sensing; Suomi NPP; VIIRS DNB; calibration
Abstract There is a growing interest in the science and user community in the Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) low light detection capabilities at night for quantitative applications such as airglow, geophysical retrievals under lunar illumination, light power estimation, search and rescue, energy use, urban expansion and other human activities. Given the growing interest in the use of the DNB data, a pressing need arises for improving the calibration stability and absolute accuracy of the DNB at low radiances. Currently the low light calibration accuracy was estimated at a moderate 15%-100% while the long-term stability has yet to be characterized. This study investigates selected existing night light point sources from Suomi NPP DNB observations and evaluates the feasibility of SI traceable nightlight source at radiance levels near 3 nW·cm−2·sr−1, that potentially can be installed at selected sites for VIIRS DNB calibration/validation. The illumination geometry, surrounding environment, as well as atmospheric effects are also discussed. The uncertainties of the ground based light source are estimated. This study will contribute to the understanding of how the Earth’s atmosphere and surface variability contribute to the stability of the DNB measured radiances, and how to separate them from instrument calibration stability. It presents the need for SI traceable active light sources to monitor the calibration stability, radiometric and geolocation accuracy, and point spread functions of the DNB. Finally, it is also hoped to address whether or not active light sources can be used for detecting environmental changes, such as aerosols.
Address NESDIS/STAR, National Oceanic and Atmospheric Administration, USA
Corporate Author Thesis
Publisher SPIE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1261
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Author Gaughan, A. E., Oda, T., Sorichetta, A., Stevens, F. R., Bondarenko, M., Bun, R., Krauser, L., Yetman, G., & Nghiem, S. V.
Title Evaluating nighttime lights and population distribution as proxies for mapping anthropogenic CO2 emission in Vietnam, Cambodia and Laos Type Journal Article
Year 2019 Publication Environmental Research Communications Abbreviated Journal
Volume 1 Issue 9 Pages (down) 091006
Keywords Remote Sensing; greenhouse gas emissions; GHG; Asia; Vietnam; Cambodia; Laos; nighttime light
Abstract Tracking spatiotemporal changes in GHG emissions is key to successful implementation of the United Nations Framework Convention on Climate Change (UNFCCC). And while emission inventories often provide a robust tool to track emission trends at the country level, subnational emission estimates are often not reported or reports vary in robustness as the estimates are often dependent on the spatial modeling approach and ancillary data used to disaggregate the emission inventories. Assessing the errors and uncertainties of the subnational emission estimates is fundamentally challenging due to the lack of physical measurements at the subnational level. To begin addressing the current performance of modeled gridded CO2 emissions, this study compares two common proxies used to disaggregate CO2 emission estimates. We use a known gridded CO2 model based on satellite-observed nighttime light (NTL) data (Open Source Data Inventory for Anthropogenic CO2, ODIAC) and a gridded population dataset driven by a set of ancillary geospatial data. We examine the association at multiple spatial scales of these two datasets for three countries in Southeast Asia: Vietnam, Cambodia and Laos and characterize the spatiotemporal similarities and differences for 2000, 2005, and 2010. We specifically highlight areas of potential uncertainty in the ODIAC model, which relies on the single use of NTL data for disaggregation of the non-point emissions estimates. Results show, over time, how a NTL-based emissions disaggregation tends to concentrate CO2 estimates in different ways than population-based estimates at the subnational level. We discuss important considerations in the disconnect between the two modeled datasets and argue that the spatial differences between data products can be useful to identify areas affected by the errors and uncertainties associated with the NTL-based downscaling in a region with uneven urbanization rates.
Address University of Louisville, Department of Geography and Geosciences, Louisville, KY, United States of America; ae.gaughan(at)louisville.edu
Corporate Author Thesis
Publisher IOP Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ intern @ Serial 2727
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